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Radeon HD 4850 512MB vs Radeon HD 4850 X2 1GB
Intro
The Radeon HD 4850 512MB uses a 55 nm design. ATi has clocked the core speed at 625 MHz. The GDDR3 RAM runs at a speed of 993 MHz on this particular card. It features 800(160x5) SPUs along with 40 TAUs and 16 ROPs.Compare all that to the Radeon HD 4850 X2 1GB, which features clock speeds of 625 MHz on the GPU, and 993 MHz on the 1024 MB of GDDR3 memory. It features 800(160x5) SPUs as well as 40 Texture Address Units and 16 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
| Radeon HD 4850 512MB |
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110 Watts |
| Radeon HD 4850 X2 1GB |
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250 Watts |
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Memory Bandwidth
Theoretically speaking, the Radeon HD 4850 X2 1GB should be 100% quicker than the Radeon HD 4850 512MB overall, because of its greater data rate. (explain)
| Radeon HD 4850 X2 1GB |
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127104 MB/sec |
| Radeon HD 4850 512MB |
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63552 MB/sec |
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Texel Rate
The Radeon HD 4850 X2 1GB is a lot (about 100%) more effective at anisotropic filtering than the Radeon HD 4850 512MB. (explain)| Radeon HD 4850 X2 1GB |
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50000 Mtexels/sec |
| Radeon HD 4850 512MB |
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25000 Mtexels/sec |
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Pixel Rate
The Radeon HD 4850 X2 1GB is much (more or less 100%) better at AA than the Radeon HD 4850 512MB, and also should be capable of handling higher screen resolutions without slowing down too much. (explain)| Radeon HD 4850 X2 1GB |
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20000 Mpixels/sec |
| Radeon HD 4850 512MB |
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10000 Mpixels/sec |
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Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.
One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.
Price Comparison
Please note that the price comparisons are based on search keywords, and might not be the exact same card listed on this page. We have no control over the accuracy of their search results.
Radeon HD 4850 512MBAmazon.com
Other US-based stores
Amazon.co.uk
Amazon.de
Amazon.fr
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Radeon HD 4850 X2 1GBAmazon.com
Other US-based stores
Amazon.co.uk
Amazon.de
Amazon.fr
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Specifications
| Model | Radeon HD 4850 512MB | Radeon HD 4850 X2 1GB |
|---|---|---|
| Manufacturer | ATi | ATi |
| Year | Jun 25, 2008 | Nov 7, 2008 |
| Code Name | RV770 PRO | R700 |
| Fab Process | 55 nm | 55 nm |
| Bus | PCIe 2.0 x16 | PCIe 2.0 x16 (PCIe bridge) |
| Memory | 512 MB | 1024 MB (x2) |
| Core Speed | 625 MHz | 625 MHz (x2) |
| Shader Speed | N/A MHz | (N/A) MHz (x2) |
| Memory Speed | 993 MHz | 993 MHz (x2) |
| Unified Shaders | 800(160x5) | 800(160x5) (x2) |
| Texture Mapping Units | 40 | 40 (x2) |
| Render Output Units | 16 | 16 (x2) |
| Bus Type | GDDR3 | GDDR3 |
| Bus Width | 256-bit | 256-bit (x2) |
| DirectX Version | DirectX 10.1 | DirectX 10.1 |
| OpenGL Version | OpenGL 3.0 | OpenGL 3.0 |
| Power (Max TDP) | 110 watts | 250 watts |
| Shader Model | 4.1 | 4.1 |
| Bandwidth | 63552 MB/sec | 127104 MB/sec |
| Texel Rate | 25000 Mtexels/sec | 50000 Mtexels/sec |
| Pixel Rate | 10000 Mpixels/sec | 20000 Mpixels/sec |
Memory Bandwidth: Memory bandwidth is the max amount of data (counted in MB per second) that can be transferred past the external memory interface in one second. It's calculated by multiplying the card's interface width by its memory speed. If the card has DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This is calculated by multiplying the total texture units of the card by the core speed of the chip. The better this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.
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